From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: ATA 4 KiB sector issues.
Date: Tue, 09 Mar 2010 21:17:08 -0800
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To: Daniel Taylor <Daniel.Taylor@wdc.com>
Cc: Tejun Heo <tj@kernel.org>, Greg Freemyer <greg.freemyer@gmail.com>, James Bottomley <James.Bottomley@suse.de>, linux-ide@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>, Jeff Garzik <jeff@garzik.org>, Mark Lord <kernel@teksavvy.com>, tytso@mit.edu, hirofumi@mail.parknet.co.jp, Andrew Morton <akpm@linux-foundation.org>, Alan Cox <alan@lxorguk.ukuu.org.uk>, irtiger@gmail.com, Matthew Wilcox <matthew@wil.cx>, aschnell@suse.de, knikanth@suse.de, jdelvare@suse.de, mkp@mkp.net
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On 03/09/2010 04:14 PM, Daniel Taylor wrote:
>
> The MBR in a GPT installation doesn't map the first GPT partition, it maps
> the entire drive
> drive after the first sector, as well as marking it type 0xEE.  The start
> LBA of the file system
> is not correctly located in the MBR.
>
> I will run some experiments to see if any of the systems on my desk can boot
> Linux from a GPT.

There is something called a "hybrid MBR", which is basically a GPT disk 
with a single partition (the current bootable partition) mapped as an 
MBR partition, instead of marking the whole disk 0xEE.

	-hpa